drseqFilter: Screen SURF training samples
In fchen365/surf: Statistical Utility for RBP (RNA binding protein) Functions

Filter DrSeq results for the analysis module 2 of SURF (DASeq).

drseqFilter(
  event,
  drseq.fdr = 0.05,
  read.length = 100,
  min.adjMean = 0.05,
  filter.overlap.event = TRUE,
  verbose = FALSE
)

`event`	a `surf` object output by drseqFit.
`drseq.fdr`	`numeric`, FDR (BH procedure) adjusted p-value cut-off.
`read.length`	`numeric`, RNA-seq read length. Default is 100 bp (e.g., Illumina TruSeq). This is used to adjust event base count, which is then used to select the representative events if replicated.
`min.adjMean`	`numeric`, adjusted event base mean threshold.
`filter.overlap.event`	`logical`, whether (default to `TRUE`) to select one representitive event from overlapping ones and remove the others.
`verbose`	`logical`, whether (default to `FALSE`) to print out basic summary statistics.

a surf object, with three columns added:

`adjMean`	adjusted base mean of the event from RNA-seq data.
`group`	group labels of ATR events, `increase` for increased REU upon RBP knock-down, and `decrease` for decreased, and `no change` for no-changed.
`included`	logical, indicating whether the event is included into SURF analysis module 2.